Silent chain



E. E. BOSWORTH.

, SILENT CHAIN. APPLICATION FILED SEPT. 18, 1919.

2 5-1 gNVE/VTOQ. I BY @Jvu 7% ATTORNEYS.

Paten ted Dec. 21,1920.

STATES EDWARD E. BOSXVORTH, 0F BERKELEY, CALIFORNIA.

SILENT CHAIN.

Specification of Letters Patent.

Patented Dec. 21, 1920.

Application filed September 18, 1919. Serial No. 324,564.

To all whom it may concern;

Be it known that I, EDWARD E. Boswonrni, a citizen of the United States, residing at Berkeley, in the county of Alameda and State of California, have invented certain new and useful Improvements in Silent Chains, of which the following is a specification.

The present invention relates to that form of structure commonly known as a V-belt or silent chain, and the principal objects of the present invention are to provide a construction which is adapted to provide the same function as the constructions now universally in use, and at the same time to have greater lasting and wear resisting qualities and be free from the fraying or buckling of the chain protecting portions, causing the separation of the same from the links should the same become oil-soaked.

A further object is to provide a construction wherein the links and protecting and friction members are capable of being readily secured together by removable means,

3 such as a screw, and wherein such removable means at its outer end is not required to pass through the entire thickness of the protecting or friction member to hold the same in contact with its associated link, as is required in constructions at present in use.

The invention consists primarily in surrounding the inner and outer side walls and the top and bottom edges of the spaced chain forming links with suitable material which incases or incloses the links, and which in turn also provides friction means for the chain, and in obtaining this result I have illustrated the invention as shown with the spaced link forming members passing through channels or longitudinal apertures in the protecting body but it is to be understood that if found convenient the upper longitudinal edge of the body may be en tirely open, which would not defeat the principal object of the present invention.

With the above mentioned and other ob jects in view, the invention consists in the novel construction and combination of parts hereinafter described, illustrated in the ac companying drawings and pointed out in the claims hereto appended; it being understood that various changes in the form, proportion, size and minor details of construction within the scope of the claims may be resorted to without departing from the spirit or sacrificing any of the advantages of. the invention.

To more fully comprehend the invention, reference is directed to the accompanying drawings, wherein Figure 1 is a view in side elevation of a pulley over which passes a portion of silent chain.

Fig. 2 is a sectional view of apair of silent chain links, the view being taken on line 22 of Fig. 3.

Fig. 3 is a vertical sectional View of the chain and pulley, taken on line 3-3 of Figs. 1 and 2.

Fig. 4 is a vertical sectional View taken on line 4l4 of Fig. 2.

Referring more particularly to the drawings, wherein like characters of reference designate corresponding parts, the numeral 1 indicates a suitable pulley, the rim 2 of which is provided with the annular substantially V-shaped groove 3 in its periphcry, and in which is received the silent chain consisting of the pivotally connected links 4.. The particular type of chain illustrated consists in alternating double plate links 5 and single plate links 6, the former being substantially flat throughout their length, and the latter provided adjacent their opposite ends with the laterally extending pintles 7 which are received in the bearing openings 8 in the plate forming links 5.

In assembling the chain, it will be observed that spacer members 9 are employed to maintain the plates forming the links 5 separated, and to permit the easy fulcrum movement between the links 5 and 6.

The side plates forming the links 5 are passed through slots or openings 10 disposed longitudinally of protecting friction members 11, preferably formed of leather, which members cover both the inner and outer side walls of the plates, and also the top and bottom longitudinal edges. Therefore, when the chain is in use, as illustrated in Fig. 3, there is no danger of the protect ing members fraying or separating from the links, as said protecting members at each side of. the respective links are united together. The plates forming the links 5 are united and held with the cooperating link pins? in the recesses 8 by a suitable removable screw 12 which passes through one plate of the respective links 5, through the memtecting members 11 in contact with the side surfaces of the respective plates of the link 5 as is the case with silent chains now in use,'a's the respective plate is passed through the opening in the protecting member, and a portion of said protecting member lies both above and below the edges of the respective plates and unites the side walls forming said member 11.

The lower edges of the plates 5 are preferably inwardly beveled, as illustrated in Figs. 3 and at, to permit the outer surfaces of the members ll to follow the contour thereof and provide a connected undcrface for each link plateinclosing member which is beveled to correspond with the bevel of the sidewalls of the groove By extending the friction or silent surfaces beneath the lower edge of each plate forming a link 5,'the lower edge of the surfaces is held on the plate,'thus protecting the plate and providing an efficient friction surface which does not render the chain useless, occasioned by the separation of the friction or silent surfaces from the plates, due to the constant wear on the chain.

By constructing the friction surfaces of non-metallic material and providing a longitudinal opening through the center thereof for receiving a chain link forming plate, the plate provides areinforcement for the friction material, and the fulcrum pin 7 connecting adjacent links extends through the friction material on the inner face of each plate 5 and also through the plate received in the opening in said friction material, as in Fig.8.

Having thus described my invention, what i I claim as new and desire to protect by Letters Patent is 1. A silent chain consisting of pivotally connected links and blocks alternating throughout the length of the chain, said links comprising spaced side plates, means for connecting said plates, and a non-metallicfriction member-extending over the lower edgeand inner wall of eachside plate for approximately the full length of said plate providing a bearing between the opposite faces of the ends of said blocks and the innerfaces of said plates.

2. A silent chain consisting of pivotally connected links and blocks alternating throughout the length of the chain, said links comprising spaced side plates, means for connecting said plates, and a non-metallic friction member extending over the lower edge of each side plate and over the outer and inner face thereof for approximately the full length of said plate providing a non-metallic bearing surface between the link plates and the block ends.

3. A silent chain consisting of pivotall connected links and blocks alternating throughout the length of the chain, said links comprising spaced side plates, means for connecting said plates, and a non-metal.- lic member inclosing the sides and upper and lower edges of each side plate for ap proximately its full length. I

i, A silent chain consisting of a plurality of pivotally connected links, certain of said links including nonsmetallic members detachably secured together, means for detachably securing said members together, and a metallic reinforcement extending through each of said non-metallic members and with which adjacent links are pivotally connected, said non-metallic members covering the inner and outer side walls of the plates and tl top and bottom edges thereof.

5. A chain link consisting of spaced metallic plates provided adjacent their ends with pintle receiving openings, a non-metallic member within which each of said plates is received, said memberseXte-nding overtlie inner and outer faces of said plates and the top and bottom edges thereof, the surface of said non-metallic members disposed adjacent the inner faces of said plates being provided with openings registering with the pintle receiving openings of the plates, a

spacer member separating said plates, and means for securing said plates in parallel relation with the spacer member positioned between the same.

In testimony whereof I have signed my name to this specification in the presence of two subscribing Witnesses.

EDlVARD E. B( )S\VORTH. lVitnesses HARRY A. Tor'rnN,

D. B. RICHARDS. 

